Sliding apparatus for sliding door

ABSTRACT

A sliding apparatus for a sliding door comprises: a front top roller part including an upper outer bracket and an upper inner bracket; a front bottom roller part including a lower outer bracket and a lower inner bracket which are fitted and fixed to both lower ends of the front door while being connected to each other by a lower connecting bar, and are formed to slide in both lateral directions after moving forward; a rear roller part including rear outer brackets and rear inner brackets which are formed at both upper ends and both lower ends of a rear door formed on one side of the front door, so as to slide the rear door; a front rail part including guide rails which are formed on the upper and lower end surfaces of a rear door frame and the upper and lower surfaces of the rear inner bracket.

BACKGROUND

The present invention relates to a sliding apparatus for a sliding doorand, more specifically, to a sliding apparatus for a sliding door, inwhich when sliding doors for opening or closing the front of furnitureor a bathroom cabinet having a storage space slide while overlappingeach other, the doors slide through the rails formed at the upper andlower ends of the rear door such that by simply coupling the doors tothe conventional rails, the front door and the rear door positioned in astraight line can be opened while overlapping each other so that thecompatibility of the product can be increased, the both doors of thesliding doors can be opened or closed at the same time so that theefficient product use is allowed, and when the doors are moved forwardor backward, the doors can move while absorbing shock so that the noiseof the product can be reduced while improving durability.

In general, various doors are provided on the front of furniture, whichhave storage spaces and thus can store articles inside, such as acabinet, a bookcase or a closet, so as to prevent the articles frombeing seen from the outside.

Such doors can be largely divided into a hinged door type and a slidingdoor type depending on the opening and closing methods thereof, whereinthe hinged door type means that a door is opened or closed while beingrotated around a rotary shaft by a hinge, and the sliding door typemeans that a door is opened or closed by the width of the door along arail.

Since the door of the hinged door type is rotated as described above, aspace corresponding to the width of the door is required, and since thesliding door type requires rails as many as the number of doors and hasto maintain a gap between such doors in order to prevent interferencebetween the doors, furniture having the sliding doors has to accommodatesuch a width for forming the doors.

In order to solve the disadvantages of the opening and closing apparatusof a sliding door as described above, an opening and closing apparatusof a sliding door has been suggested in Korean Patent Registration No.1180469.

The opening and closing apparatus of a sliding door as described abovecan slide in both lateral directions and can be stably and smoothlyopened and closed with minimized frictional resistance at the time ofmovement in the back and forth directions, thereby carrying out furtherstabilized movement in the back and forth directions.

However, this prior art has problems in that in order to ensuring theback and forth movement of the door in the sliding door as describedabove, a rail frame has to include a straight rail and a curved railprotruding forward so that additional rails have to be installed,resulting in a complicate structure while decreasing productivity.

In addition, since the both side doors have the same tracks along whichthe doors slide and move back and forth, the both side doors cannot beopened or closed at the same time so that the product efficiency isdecreased. Further, since there is no damper for the shock at the timeof the back and forth movement of the doors, there are further problemsthat noise is generated at the time of sliding the doors and thedurability of the product is lowered by the shock.

SUMMARY OF THE INVENTION

Accordingly, the present invention has been made in an effort to solvethe above-mentioned problems and disadvantages occurring in the priorarts and has an objective to provide a sliding apparatus for a slidingdoor, in which when the sliding doors slide and overlap each other, bysimply coupling the doors to the conventional rail, the front door andthe rear door positioned in a straight line can be opened whileoverlapping each other, thereby increasing the compatibility of theproduct.

It is another objective of the present invention to provide a slidingapparatus for a sliding door, in which the both doors of the slidingdoors can be opened or closed at the same time so that it is possible touse articles stored in either side of furniture or a bathroom cabinet,thereby enabling efficient product use, and when the doors are moveforward or backward, the doors can move while absorbing shock so thatthe noise of the product can be reduced while improving durability.

According to the present invention to achieve the above objectives inorder to achieve the above-mentioned objectives, there is provided asliding apparatus for a sliding door, comprising: a front top rollerpart including an upper outer bracket and an upper inner bracket whichare fitted and fixed to both upper ends of a front door while beingconnected to each other by an upper connecting bar, and are formed toslide in both lateral directions after moving forward; a front bottomroller part including a lower outer bracket and a lower inner bracketwhich are fitted and fixed to both lower ends of the front door whilebeing connected to each other by a lower connecting bar, and are formedto slide in both lateral directions after moving forward; a rear rollerpart including rear outer brackets and rear inner brackets, which areformed at both upper ends and both lower ends of a rear door formed onone side of the front door, so as to slide the rear door; a front railpart including guide rails which are formed on the upper and lower endsurfaces of a rear door frame and the upper and lower surfaces of therear inner bracket, such that the upper inner bracket of the front toproller part and the lower inner bracket of the front bottom roller partslide while moving forward along the guide rails; and a straight railpart including straight rails, which are formed at the upper and lowerends of a housing, so as to slide the front door and the rear door inboth lateral directions.

Each of the upper outer bracket and the upper inner bracket of the fronttop roller part includes upper straight rollers formed at the front andrear portions of the bottom surface of an upper straight body so as toslide along the straight rail of the straight rail part, upper movementbodies are fitted and fixed to both sides of the upper end of the frontdoor so as to slide back and forth by bearings on the inside of theupper straight body, thereby guiding the forward movement of the frontdoor, a damper is formed on the bottom surface of the upper straightbody and elastically mounted by a restoring spring, which is connectedto the upper straight body and one side of the upper movement body, soas to absorb shock during the movement of the upper movement body, andan upper movement roller is formed on the rear door side of the upperinner bracket so as to move along the guide rail.

The lower outer bracket of the front bottom roller part has a lowerstraight roller formed on the top surface of a lower straight body so asto slide along the straight rail, a lower movement body is fitted andfixed to the outside of the lower end of the front door so as to slideon the outside of the lower straight body and guide the forward movementof the front door, the outside of the lower movement body and the lowerstraight body are elastically mounted by a restoring spring, and a lowermovement roller is formed on the rear door side of the lower innerbracket so as to move along the guide rail.

Each of the rear outer bracket and the rear inner bracket of the rearroller part includes a rear horizontal roller and connecting rod rollersare formed on the front door side of the rear inner bracket so as tocome into rolling contact with the rear portions of the connecting barsand thus slide.

A damping latch is formed to be extended from the rear side of each ofthe rear outer bracket and the rear inner bracket, which are formed onthe lower end of the rear door of the rear roller part, so as to be heldby a damper.

A handle is formed on each of the bottom surfaces of the rear outerbracket formed at the lower end of the rear door of the rear roller partand the lower outer bracket of the front bottom roller part so as toprotrude to the lower portion of each of the front door and the reardoor.

The guide rail formed on the rear door frame of the front rail part isformed to be straight and the guide rail of the rear inner bracket,which is connected to the guide rail, is formed as a curved rail that iscurved backward.

The upper straight roller is formed to be parallel to the front door andthe upper movement roller is formed to be perpendicular.

A latch is formed on the rear side of the upper straight body of each ofthe upper outer bracket and the upper inner bracket so as to be held bya damper.

The lower straight roller and the lower movement roller are formed to beperpendicular to the front door.

The rear horizontal roller formed on each of the rear outer bracket andthe rear inner bracket at the upper end of the rear door of the rearroller part is formed to be parallel to the rear door, and theconnecting rod and the rear horizontal roller formed on the rear innerbracket and the rear outer bracket at the lower end of the rear door areformed to be perpendicular to the rear door.

As described above, according to the present invention, when the slidingdoors slide and overlap each other, by simply coupling the doors to theconventional rail, the front door and the rear door positioned in astraight line can be opened while overlapping each other, therebyincreasing the compatibility of the product, the both doors of thesliding doors can be opened or closed at the same time so that it ispossible to use articles stored in either side of furniture or abathroom cabinet, thereby enabling efficient product use, and when thedoors are moved forward or backward, the doors can move while absorbingshock so that the noise of the product can be reduced while improvingdurability.

While the present invention has been particularly shown and describedwith reference to exemplary embodiments thereof, it is to be understoodthat the invention is not limited to the disclosed exemplaryembodiments, but, on the contrary, various changes and modifications maybe made within the spirit of the present invention by those skilled inthe art, to which the present invention belongs.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is an exploded perspective view showing an upper outer bracket ofa sliding apparatus for a sliding door according to the presentinvention,

FIG. 2 is an exploded perspective view showing an upper inner bracket ofa sliding apparatus for a sliding door according to the presentinvention,

FIG. 3 is a cross-sectional view showing an upper inner bracket of asliding apparatus for a sliding door according to the present invention,

FIG. 4 is an exploded perspective view showing a lower inner bracket ofa sliding apparatus for a sliding door according to the presentinvention,

FIG. 5 is an exploded perspective view showing a lower outer bracket ofa sliding apparatus for a sliding door according to the presentinvention,

FIG. 6 is an exploded perspective view showing a front door of a slidingapparatus for a sliding door according to the present invention,

FIG. 7 is a perspective view showing a front door of a sliding apparatusfor a sliding door according to the present invention,

FIG. 8 is an exploded perspective view showing a rear inner bracket atthe upper end of a rear door of a sliding apparatus for a sliding dooraccording to the present invention,

FIG. 9 is an exploded perspective view showing a rear outer bracket atthe upper end of a rear door of a sliding apparatus for a sliding dooraccording to the present invention,

FIG. 10 is an exploded perspective view showing a rear inner bracket atthe lower end of a rear door of a sliding apparatus for a sliding dooraccording to the present invention,

FIG. 11 is an exploded perspective view showing a rear outer bracket atthe lower end of a rear door of a sliding apparatus for a sliding dooraccording to the present invention,

FIG. 12 is an assembled perspective view showing a rear door accordingto a sliding apparatus for a sliding door according to the presentinvention,

FIG. 13 is an explanatory view showing the upper and lower outerbrackets of a sliding apparatus for a sliding door according to thepresent invention, when doors are closed,

FIG. 14 is an explanatory view showing the upper and lower innerbrackets of a sliding apparatus for a sliding door according to thepresent invention, when doors are closed,

FIG. 15 is a perspective view showing a sliding apparatus for a slidingdoor according to the present invention, which is applied to a straightrail,

FIG. 16 is a cross-sectional view showing a sliding apparatus for asliding door according to the present invention, which is applied to astraight rail,

FIG. 17 is a plane view showing a closed state of a sliding apparatusfor a sliding door according to the present invention,

FIG. 18 is a plane view showing an opened state of a sliding apparatusfor a sliding door according to the present invention,

FIG. 19 is an explanatory view showing the upper inner end surface of asliding apparatus for a sliding door according to the present invention,when doors are closed,

FIG. 20 is an explanatory view showing the lower inner end surface of asliding apparatus for a sliding door according to the present invention,when doors are closed, and

FIG. 21 is an assembly diagram of a sliding apparatus for a sliding dooraccording to the present invention.

BRIEF EXPLANATION OF REFERENCE SYMBOLS

10: front top roller part 11: front door 12: upper outer bracket 13:upper inner bracket 14: upper connecting bar 20: front bottom rollerpart 21: lower outer bracket 22: lower inner bracket 23: lowerconnecting bar 30: rear roller part 31: rear door 32: rear outer bracket33: rear inner bracket 40: front rail part 41: guide rail 50: straightrail part 51: straight rail 60: handle

DETAILED DESCRIPTION OF THE INVENTION

In order to fully understand the advantages in the operations of thepresent invention and the objectives achieved by the implementation ofthe present invention, reference should be made to the accompanyingdrawings, which show preferred embodiments of the present invention, andthe contents of the accompanying drawings.

Hereinafter, the present invention will be described in more detail withreference to specific examples of the present invention. The followingexamples are provided to explain the present invention in more detail,but the technical scope of the present invention is not limited thereto.

Embodiments

FIG. 18 is an assembly diagram showing a sliding apparatus for a slidingdoor according to the present invention.

As illustrated, a sliding apparatus for a sliding door according to thepresent invention includes a front top roller part 10 and a front bottomroller part 20 for opening or closing a front door 11, a rear rollerpart 30 formed on a rear door 31, a front rail part 40 along which thefront top roller part 10 and the front bottom roller part 20 slide, anda straight rail part 50 along which the front and rear doors 11, 31slide.

As shown in FIG. 1 to FIG. 3, the front top roller part 10 as describedabove includes an upper outer bracket 12 and upper inner bracket 13which are fitted and fixed to both upper ends of the front door 11 whilebeing connected to each other by an upper connecting bar 14.

The upper outer bracket 12 and the upper inner bracket 13 of the fronttop roller part 10 include upper straight rollers 16 formed at the frontand rear portions of the bottom surface of an upper straight body 15 soas to slide along the straight rail 51 of the straight rail part 50, andupper movement bodies 17 are fitted and fixed to both sides of the upperend of the front door 11 so as to slide back and forth by bearings B onthe inside of the upper straight body 15, thereby guiding the forwardmovement of the front door 11.

A damper 18 is formed on the bottom surface of the upper straight body15 and elastically mounted by a restoring spring S, which is connectedto the upper straight body 15 and one side of the upper movement body17, so as to absorb shock during the movement of the upper movement body17, and an upper movement roller 19 is formed on the inside andperpendicular to the front door 11.

In addition, a latch 15′ is formed on the rear side of the upperstraight body 15 of each of the upper outer bracket 12 and the upperinner bracket 13 so as to be held by a damper formed at the upper sideof a housing.

The front bottom roller part 20 is formed at both sides on the lower endof the front door 11 respectively.

As shown in FIG. 4 to FIG. 5, the front bottom roller part 20 as aboveincludes a lower outer bracket 21 and a lower inner bracket 22 which arefitted and fixed to both sides of the lower end of the front door 11while being connected to each other by a lower connecting bar 23, andare formed to slide in both lateral directions after moving forward.

The lower outer bracket 21 of the front bottom roller part 20 asdescribed above includes a lower straight roller 25, which is formed onthe top surface of a lower straight body 24 so as to slide along thestraight rail 51, and a lower movement body 26, which is fitted andfixed to the outside of the lower end of the front door 11 so as toslide on the outside of the lower straight body 24 and thus guide theforward movement of the front door 11.

The outside of the lower movement body 26 and the lower straight body 24are elastically mounted by a restoring spring S, and a lower movementroller 27 is formed on the lower inner bracket 22 so as to beperpendicular to the front door 11.

The rear roller part 30 is formed on the rear door 31 formed at one sideof the front door 11.

As shown in FIG. 8 to FIG. 12, the rear roller part 30 includes rearouter brackets 32 and rear inner brackets 33 which are formed at bothupper ends and both lower ends of the rear door 31 so as to slide therear door 31.

Each of the rear outer bracket 32 and the rear inner bracket 33 of therear roller part 30 includes a rear horizontal roller 34 and aconnecting rod roller 35 is formed on the front door 11 side of the rearinner bracket 33 so as to come into rolling contact with the rearportion of the connecting bar 23 and thus slide.

In addition, a damping latch 36 is formed to be extended from the rearside of each of the rear outer bracket 32 and the rear inner bracket 33,which are formed on the lower end of the rear door 31 of the rear rollerpart 30, so as to be held by a damper.

A handle 60 is formed on each of the bottom surfaces of the rear outerbracket 31 formed at the lower end of the rear door 31 of the rearroller part 30 and the lower outer bracket 21 of the front bottom rollerpart 20 so as to protrude to the lower portion of each of the front door11 and the rear door 31.

The rear horizontal roller 34 formed on each of the rear outer bracket32 and the rear inner bracket 33 at the upper end of the rear door 31 ofthe rear roller part 30 is formed to be parallel to the rear door 31,and the connecting rod roller 35 and the rear horizontal roller 34formed on the rear inner bracket 33 and the rear outer bracket 32 at thelower end of the rear door 31 are formed to be perpendicular to the reardoor 31.

The front rail part 40 is formed such that the upper inner bracket 13 ofthe front top roller part 10 and the lower inner bracket 22 of the frontbottom roller part 20 slide while moving forward.

The front rail part 40 includes guide rails 41 which are formed on theupper and lower end surfaces of a rear door frame 34 and the upper andlower surfaces of the rear inner bracket 33, wherein the guide rail 41formed on the rear door frame 34 of the front rail part 40 is formed tobe straight and the guide rail 41 of the rear inner bracket 33, which isconnected to the guide rail 41, is formed as a curved rail that iscurved backward.

Meanwhile, as shown in FIG. 15 to FIG. 16, the straight rail part 50 isformed such that the front door 11 and the rear door 31 slide in bothlateral directions, wherein the straight rail part 50 includes thestraight rails 51 formed on the upper and lower ends of the housing.

The operation and effect of the present invention structured as abovewill be described below.

First, the front door 11 and the rear door 31 are formed on the frontsurface of the housing, which has a storage space.

In order to locate the front door 11 and the rear door 31 on the samestraight line when the housing is closed and to maintain the front door11 and the rear door 31 in an overlapping state when opened by slidingdoors, as shown in FIG. 18, the front door 11 and the rear door 13 aremaintained in the overlapping state while the upper outer bracket 12 andthe upper inner bracket 13, which are fixed to the front door 11, andthe upper movement body 17 and the lower movement body 26 of the lowerouter bracket 21 slidingly move forward.

Herein, in order to enable the front door 11 to overlap the rear door 31in front of the rear door 31, the upper movement roller 19 formed on theupper movement body 17 of the upper inner bracket 13 moves along theupper end surface of the rear door frame 34 of the rear door 31 and theguide rail 41 formed on the upper surface of the rear inner bracket 33,and the lower movement roller 27 formed on the lower inner bracket 22moves along the lower end surface of the rear door frame 34 of the reardoor 31 and the guide rail 41 formed on the lower surface of the rearinner bracket 33.

The front door 11 is opened or closed while moving forward along theguide rail 41 as described above.

When the front door 11 moves as described above, the connecting rodrollers 35 formed on the rear inner brackets 33 come into rollingcontact with the rear portions of the upper connecting bar 14, whichconnects the upper outer bracket 12 and the upper inner bracket 13 fixedon the front door 11, and the lower connecting bar 23, which connectsthe lower outer bracket 21 and the lower inner bracket 22, therebyincreasing stability during opening or closing.

The front door 11 and the rear door 31 are opened while overlapping eachother even if the front door 11 and the rear door 31 are openedsimultaneously, as the front door 11 moves along the guide rail 41formed on the rear door 31 as described above.

The upper movement roller 19 formed on the upper end of the front door11 and the connecting rod roller 35 formed on the rear door 31, whichmove as above as shown in FIG. 19 an FIG. 20, come into surface contactwith each other without any planar gap between the rollers such that thedoors can be opened or closed stably without shaking and the front door11 and the rear door 31 can be opened or closed simultaneously whilerolling.

In addition, the lower movement roller 27 and the connecting rod roller35 on the inner rear ends of the front door 11 and the rear door 31,which are opened and closed as described above, are formed to rollwithout any planar gap between the rollers such that the doors can beopened or closed stably without shaking and the front door 11 and therear door 31 can be simultaneously opened or closed simultaneously whilerolling.

Further, the upper straight rollers 16, which are formed on the upperstraight bodies 15 of the upper outer bracket 12 and the upper innerbracket 13 of the front door 11, and the lower straight roller 25 on thelower straight body 24 of the lower outer bracket 21 slide along thestraight rails 51.

The rear horizontal rollers 34 formed on the rear outer bracket 32 andthe rear inner bracket 33 come into rolling contact with the straightrail 51 and slide along the straight rail 51 such that the rear door 31moves.

If the front door 11 and the rear door 31 overlap as described above,the restoring spring S which is formed on the upper straight body 15 andthe upper movement body 17 and the restoring spring S which connects thelower straight body 24 and the lower movement body 25 are maintained ina tensioned state.

If the front door 11 and the rear door 31 are positioned on the sameline in this state so as to close the housing, the front door 11 and therear door 31 slide in the same manner as the sliding manner describedabove and the upper straight body 15 and the upper movement body 17 aswell as the lower straight body 24 and the lower movement body 25 areinserted into and returned to the original positions thereof by therestoring force of the restoring spring S which is formed on the upperstraight body 15 and the upper movement body 17 and the restoring springS which connects the lower straight body 24 and the lower movement body25

Herein, the shock when the front door 11 is returned to the originalposition thereof is absorbed as the damper 18 formed on the bottomsurface of the upper straight body 15 absorbs the shock in the movementof the upper movement body 17.

The opening or closing of the doors as described above can be carriedout by holding the handles 60 formed on the rear outer bracket 31 andthe lower outer bracket 21 so that the opening or closing can be carriedout conveniently, and the latch 15′ of the upper straight body 15 andthe damping latches 36 formed on the rear side of the rear outer bracket32 and the rear inner bracket 33 are formed to be held on the damperformed on the upper and lower ends of the housing such that the shock atthe time of opening or closing the doors can be absorbed.

The invention claimed is:
 1. A sliding apparatus for a sliding door,comprising: a front top roller part (10) including an upper outerbracket (12) and an upper inner bracket (13) which are fitted and fixedto both upper ends of a front door (11) while being connected to eachother by an upper connecting bar (14), and are formed to slide in bothlateral directions after moving forward; a front bottom roller part (20)including a lower outer bracket (21) and a lower inner bracket (22)which are fitted and fixed to both lower ends of the front door (11)while being connected to each other by a lower connecting bar (23), andare formed to slide in both lateral directions after moving forward; arear roller part (30) including rear outer brackets (32) and rear innerbrackets (33) which are formed at both upper ends and both lower ends ofa rear door (31) formed on one side of the front door (11), so as toslide the rear door (31); a front rail part (40) including guide rails(41) which are formed on the upper and lower end surfaces of a rear doorframe (34) and the upper and lower surfaces of the rear inner bracket(33), such that the upper inner bracket (13) of the front top rollerpart (10) and the lower inner bracket (22) of the front bottom rollerpart (20) slide while moving forward along the guide rails (41); and astraight rail part (50) including straight rails (51) which are formedat the upper and lower ends of a housing, so as to slide the front door(11) and the rear door (31) in both lateral directions.
 2. The slidingapparatus for a sliding door according to claim 1, wherein each of theupper outer bracket (12) and the upper inner bracket (13) of the fronttop roller part (10) includes upper straight rollers (16) formed at thefront and rear portions of a bottom surface of an upper straight body(15) so as to slide along the straight rail (51) of the straight railpart (50), upper movement bodies (17) are fitted and fixed to both sidesof the upper end of the front door (11) so as to slide back and forth bybearings on an inside of the upper straight body (15), thereby guidingthe forward movement of the front door (11), a damper (18) is formed ona bottom surface of the upper straight body (15) and elastically mountedby a restoring spring (S), which is connected to the upper straight body(15) and one side of the upper movement body (17), so as to absorb shockduring the movement of the upper movement body (17), and an uppermovement roller (19) is formed on the rear door (31) side of the uppermovement body (17) of the upper inner bracket (13) so as to move alongthe guide rail (41).
 3. The sliding apparatus for a sliding dooraccording to claim 2, wherein the upper straight roller (16) is formedto be parallel to the front door (11) and the upper movement roller (19)is formed to be perpendicular.
 4. The sliding apparatus for a slidingdoor according to claim 2, wherein a latch (15’) is formed on a rearside of the upper straight body (15) of each of the upper outer bracket(12) and the upper inner bracket (13) so as to be held by a damper. 5.The sliding apparatus for a sliding door according to claim 1, whereinthe lower outer bracket (21) of the front bottom roller part (20) has alower straight roller (25) formed on a top surface of a lower straightbody (24) so as to slide along the straight rail (51), a lower movementbody (26) is fitted and fixed to an outside of the lower end of thefront door (11) so as to slide on an outside of the lower straight body(24) and guide the forward movement of the front door (11), an outsideof the lower movement body (26) and the lower straight body (24) areelastically mounted by a restoring spring (S), and a lower movementroller (27) is formed on the rear door (31) side of the lower innerbracket (22) so as to move along the guide rail (41).
 6. The slidingapparatus for a sliding door according to claim 5, wherein the lowerstraight roller (25) and the lower movement roller (27) are formed to beperpendicular to the front door (11).
 7. The sliding apparatus for asliding door according to claim 1, wherein each of the rear outerbracket (32) and the rear inner bracket (33) of the rear roller part(30) includes a rear horizontal roller (34) so as to slide along thestraight rail (51), and connecting rod rollers (35) are formed on thefront door (11) side of the rear inner brackets (33) so as to come intorolling contact with the rear portion of the upper connecting bar (14)and the lower connecting bar (23) and thus slide.
 8. The slidingapparatus for a sliding door according to claim 7, wherein the rearhorizontal roller (34) formed on each of the rear outer bracket (32) andthe rear inner bracket (33) at the upper end of the rear door (31) ofthe rear roller part (30) is formed to be parallel to the rear door(31), and the connecting rod roller (35) and the rear horizontal roller(34) formed on the rear inner bracket (33) and the rear outer bracket(32) at a lower end of the rear door (31) are formed to be perpendicularto the rear door (31).
 9. The sliding apparatus for a sliding dooraccording to claim 1, wherein a damping latch (36) is formed to beextended from an rear side of each of the rear outer bracket (32) andthe rear inner bracket (33), which are formed on the lower end of therear door (31) of the rear roller part (30), so as to be held by adamper.
 10. The sliding apparatus for a sliding door according to claim1, wherein a handle (60) is formed on each of a bottom surfaces of therear outer bracket (31) formed at the lower end of the rear door (31) ofthe rear roller part (30) and the lower outer bracket (21) of the frontbottom roller part (20) so as to protrude to the lower portion of eachof the front door (11) and the rear door (31).
 11. The sliding apparatusfor a sliding door according to claim 1, wherein the guide rail (41)formed on the rear door frame (34) of the front rail part (40) is formedto be straight and the guide rail (41) of the rear inner bracket (33),which is connected to the guide rail (41), is formed as a curved railthat is curved backward.